no92-98

[97] Measuring Compactness of Residence in Japanese Local Living-Sphere by Road Time-Distance

○Kei Fukuyama¹, Tomoo Aoki¹, Yuki Ohira² (1. Tottori University, 2. Tokyo Metropolitan University)

Keywords:Compact city, population gravity center, road network, GIS

The urban policy on compactness of the core city and enhanced access to the core city from the surrounding local towns in the living-sphere are planned and implemented by many local governments in Japan. This research proposes a method to measure the road accessibility of the residents. The method is the expansion of Weber point. While Weber point uses direct distances to obtain the center, our population center uses the actual road time-distances. The average time-distance from a town to the population center also teaches us if the increase in population of the town can contribute to the overall road accessibility of the living area. The proposed method is applied to the living area of the eastern Tottori Prefecture in Japan in 2010 and 2015. Especially, it is clarified that while the accessibility of the living area as a whole had progressed, the number of towns regarded as ‘accessibility-improving’ areas had decreased in the five years.